A new compound of the following structural formula I has been disclosed in Chinese Patent NO. CN 91107318.3 (applicant: Shanghai Zhong Xi Pharmaceutical Co., Ltd.) ##STR1##
The compound of formula I has the common name Flubrocythrinate, and its chemical name is .alpha.-cyano-3-(4-bromophenoxy) benzyl-2-(4-difluoromethoxyphenyl)-3-methylbutyrate.
Flubrocythrinate possesses relatively high insecticidal and miticidal activities and excellent efficacy in comparison with ordinary pyrethroidal pesticides known in prior art, Flubrocythrinate also shows low toxicities towards human and animals and low toxicities towards beneficial insects and animals, in other words, said compound possesses very high insecticidal and miticidal activities and selectivities.
The inventor of the present invention has made efforts in increasing the efficacy and decreasing the dosage of the compound described above. The inventor notes that there are two chiral carbons in the structure formula of compound I, it consists of four optically active isomers. The inventor found, that the efficacy illustrated by an insecticidal and miticidal agents using the racemic form of the compound I as the active ingredient is lower than that using a specific optically active isomer. The dosage of the racemic form of the compound I used is greater than that of a single optically active isomer used, therefore increasing the environmental pollution.